Updating i/o progress while saving Gnumeric XML file.
Updating i/o progress while saving Gnumeric XML file. * src/xml-io.c s/N_ELEMENTS_BETWEEN_UPDATES/N_INPUT_ELEMENTS_BETWEEN_UPDATES (xml_write_cell_and_position): Update i/o progress every N_OUTPUT_ELEMENTS_BETWEEN_UPDATES cells. (xml_write_styles): Ditto for styles. (gnumeric_xml_read_workbook): Better error reporting. (workbook_get_n_elements): Internal function, calculating the number of "elements" (styles and cells) in workbook. (gnumeric_xml_write_workbook): Split saving to three stages: building XML tree, dumping it to memory buffer, saving (compressed) buffer contents to file. Update i/o progress regularly. The second stage still freezes UI though :(